Functional gastrointestinal disorders (FGIDs) are extremely common in children and adolescents, and represent a wide range of disorders that are related to the gastrointestinal tract, but have no clear structural, anatomic, or histopathologic cause. FGIDs represent an enormous burden on patients and families, and patients with these functional disorders have much higher health care utilization and related costs. As there are no biochemical markers or structural abnormalities that can be used to diagnose these disorders in children objectively, FGIDs are diagnosed according to the symptom-based Rome criteria. While gastroenterologists care for many of the pediatric patients with FGIDs, the majority of the burden continues to be borne by general pediatricians, especially with respect to initial diagnosis. Unfortunately, FGIDs are often diagnosed incorrectly by primary care providers, and patients often wait months to years before a correct diagnosis is made, and effective treatment is begun. Furthermore, primary care providers are often unaware of recent guideline changes or the evidence base for children with FGIDs, leading to overuse of testing, inappropriate or ineffective treatment, and increased costs. Given this information, it is essential that we develop interventions that target pediatric primary care providers to improve their care for children with FGIDs. We propose that using a Clinical Decision Support System (CDSS) that incorporates the Rome IV criteria for diagnosis and evidence-based care for FGIDs will improve the (1) accuracy of diagnosis and (2) effectiveness of clinical care. A CDSS has advantages with respect to guideline adherence and automated diagnosis, because it can provide focused, real-time, patient-specific data to the clinician. Studies of barriers to guideline implementation have shown multiple factors at work: unfamiliarity with a guideline, lack of self-efficacy, or difficulty implementing the guideline components within the current workflow of a practice. CDSS can overcome many of these barriers because they are integrated with systems that routinely store and retrieve patient information and can improve workflow by providing clinicians with patient-specific advice at the time of the patient visit. Our research group at IUSM has previously developed an efficient, robust, highly accurate computerized CDSS for use in the primary care setting: the Child Health Improvement through Computerized Automation (CHICA) system. We hypothesize that automation of screening, diagnosis, and management of FGIDs using the Rome IV criteria will result in improved resolution of FGIDs (primary outcome), as well as decreased utilization of medical services (secondary outcomes). We propose to test this hypothesis using the following specific aims: (1) Expand and modify an existing computer-based decision support system (CHICA), to screen children 0 to 18 years of age for functional gastrointestinal disorders (FGIDs) using the Rome IV criteria, and provide guidance regarding diagnosis and management of probable FGIDs; and (2) Demonstrate the feasibility and effectiveness of this CHICA FGID Module to improve clinical care measures and reduce utilization of healthcare services.